Flagship guide · 8 min read
The Ultimate Guide to Sliding Doors
How aluminium sliding doors work, what separates a good system from a poor one, and what to expect from specification through to installed cost.
Bifold Door Buying Guide
A practical guide to choosing bifold doors: configurations, tracks and thresholds, glass, and how they compare with sliding doors for cost and everyday use.
3 min read
Bifold doors fold back like a concertina, opening the full width of the aperture and turning an ordinary wall into an open connection between a kitchen, garden room or extension and the outside. They suit homes that genuinely use the whole opening, not just a single door's width of it.
This guide covers the practical decisions: how many panels, which way they fold, top-hung or bottom-rolling running gear, threshold choice, and what a realistic budget looks like once glass and hardware are specified properly.
Panel configurations
Bifold panels are typically 700-1000mm wide each, and the total number across an opening determines both the price and how the door stacks when open. An odd number of panels usually includes one that also serves as a hinged access door — a 'traffic door' — so you do not need to open the whole set just to nip outside.
- 3-panel — good for openings up to around 3m, simple and cost-effective
- 4-5 panel — the most common configuration for 4-5m extensions and garden rooms
- 6+ panel — very wide openings, panels stack to one or both sides
- Include a traffic door if the set will mostly stay closed day to day
| Configuration | Approximate width | Typical price range |
|---|---|---|
| 3-panel | Around 3m | £7,000 - £12,000 |
| 4-5 panel | 4 - 5m | £10,000 - £18,000 |
Tracks, thresholds and running gear
Bottom-rolling systems, where the weight of the panels runs on a track set into the cill, are the most common and generally the more affordable option. Top-hung systems suspend the panels from a track at the head, keeping the cill area completely clear, which suits step-free access but costs more and needs a structurally sound head to carry the load.
Glass and security
As with sliding doors, glass does most of the thermal and acoustic work on a bifold, and toughened or laminated safety glass is required below 800mm from finished floor level under Part K. Multi-point locking on the traffic door and shoot bolts on the remaining panels are standard on a properly specified system, and PAS 24 rated hardware is worth requesting even where it is not a strict planning requirement.
- Low-e double or triple glazing with warm-edge spacers as standard
- Toughened or laminated glass below 800mm from floor level
- Multi-point locking engaging into the head and cill, not just the meeting stiles
- PAS 24 rated hardware for new build and added security peace of mind
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Relevant colours
Colours StudioAnthracite Grey · RAL 7016Jet Black · RAL 9005
Suitable glass
Glass Studio
Clear Glass
Solar ControlRelated hardware
Hardware Studio
Pull Bars
ThresholdsQuestions
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